<template>
  <div class="star" :class="startType">
    <span v-for="(itemClass, index) in itemClasses" v-bind:key="index" :class="itemClass" class="star-item"></span>
  </div>
</template>

<script type="text/ecmascript-6">
const LENGTH = 5; // 总的星星的个数
const CLS_ON = 'on';
const CLS_HALF = 'half';
const CLS_OFF = 'off';

// 星星DOM组件
export default {
  name: 'star',
  props: {
    size: { // 星星尺寸大小
      type: String,
    },
    score: {
      type: Number,
    },
  },
  computed: {
    startType() {
      return 'star-' + this.size
    },
    itemClasses() {
      const result = []
      const score = Math.floor(parseFloat(this.score) * 2) / 2
      const hasDecimal = score % 1 !== 0
      const scoreI = Math.floor(score)

      for (let i = 0; i < scoreI; i++) {
        result.push(CLS_ON)
      }
      if (hasDecimal) {
        result.push(CLS_HALF)
      }
      while (result.length < LENGTH) {
        result.push(CLS_OFF)
      }
      return result
    },
  },
}
</script>

<style lang="stylus" rel="stylesheet/stylus">
  @import "../../common/stylus/mixin"
  .star
    .star-item
      display: inline-block
      background-repeat: no-repeat
    &.star-48
      .star-item
        width: 20px
        height: 20px
        margin-right: 10px
        background-size: 20px 20px
        &:last-child
          margin-right: 0
        &.on
          bg-image('star48_on')
        &.half
          bg-image('star48_half')
        &.off
          bg-image('star48_off')
    &.star-36
      .star-item
        width: 15px
        height: 15px
        margin-right: 5px
        background-size: 15px 15px
        &:last-child
          margin-right: 0
        &.on
          bg-image('star36_on')
        &.half
          bg-image('star36_half')
        &.off
          bg-image('star36_off')
    &.star-24
      .star-item
        width: 10px
        height: 10px
        margin-right: 3px
        background-size: 10px 10px
        &:last-child
          margin-right: 0
        &.on
          bg-image('star24_on')
        &.half
          bg-image('star24_half')
        &.off
          bg-image('star24_off')
</style>
